Transmissive dark-field illumination method for high-accuracy automatic lace scalloping

Abstract

A vision system has been developed to facilitate the pulsed-laser cutting of decorative lace used in various forms of apparel. Existing vision systems for lace cutting utilise back-lighting or top-lighting techniques to create a near-binary image of the lace. This can lead to problems in identifying the lace cutting path accurately. A transmissive illumination system has been modelled and tested that can reveal density information from the lace, and so, provide a more suitable image for identifying cutting points on the lace web. Experimental results have demonstrated that the illumination method can be successfully modelled to ensure even illumination using light emitting diodes (LED).